Hitherto, various acidic drinks containing soybean products such as soy milk or tofu paste have been developed, but the product characteristics such as texture and flavor of such acidic drinks containing soybean products have varied greatly according to the type and properties of the soybean product used as a raw material.
Hitherto, various manufacturing techniques have been developed for such soybean products and acidic drinks containing these soybean products. Out of these, first, as manufacturing techniques for soybean products such as tofu paste, for example, 1) a method in which tofu is made into a paste using a silent cutter or the like and then frozen (Japanese Patent Application Laid-open No. 6-46784, hereinafter referred to as ‘Prior Art 1’), 2) a method in which a coagulum obtained by adding a coagulating agent to soy milk is drained and then made into a paste using a high-speed cutter or the like (Japanese Patent Application Laid-open No. 2-86747, hereinafter referred to as ‘Prior Art 2’), and 3) a method in which a coagulating agent is added to soy milk and then processing with a homogenizer is carried out to produce a homogenized paste (Japanese Patent Application Laid-open No. 59-71641, hereinafter referred to as ‘Prior Art 3’) have been proposed.
Next, as techniques for manufacturing acidic drinks containing soybean products such as soy milk and tofu paste, for example 4) a method of manufacturing an acidic soy milk drink in which a soy protein liquid extract obtained by adding a stabilizer and so on to a soy protein liquid extract and then adding and mixing in a fruit juice or an acidulant to the resulting solution is used as a principal raw material (Japanese Patent Application Laid-open No. 58-13358, hereinafter referred to as ‘Prior Art 4’), 5) a method of manufacturing an acidic soy milk drink in which soy milk to which a high methoxyl pectin has been added is used as a raw material base (Japanese Patent Application Laid-open No. 58-183060, hereinafter referred to as ‘Prior Art 5’), 6) a method of manufacturing an acidic protein drink in which tamarind seed gum polysaccharide and/or guar gum and a pectin are used together as stabilizers (Japanese Patent Application Laid-open No. 60-256372, hereinafter referred to as ‘Prior Art 6’), 7) a method of manufacturing a fruit juice-containing soy milk drink in which an acidic fruit juice is added or an acidic fruit juice and an organic acid are added to soy milk that has been fermented using lactic acid bacteria (Japanese Patent Application Laid-open No. 61-141840, hereinafter referred to as ‘Prior Art 7’), 8) a method of manufacturing an acidic milk drink in which a pectin and gum arabic are used together as stabilizers (Japanese Patent Application Laid-open No. 10-313781, hereinafter referred to as ‘Prior Art 8’), and 9) a method of manufacturing a lactic acid-fermented soy milk characterized in that a coagulating agent is added to soy milk, the soy milk is heated and then homogenized, and then the soy milk is subjected to lactic acid fermentation (Japanese Patent Application Laid-open No. 2000-93083, hereinafter referred to as ‘Prior Art 9’) have been proposed.
However, in general, with a conventional tofu paste, tofu is made into a paste either as is or after having been drained (i.e. after the tofu has been completely coagulated), and hence the tofu paste obtained inevitably has the following properties: 1) a viscosity exceeding 3,000 mPa·s, 2) a dynamic storage modulus exceeding 600 Pa, 3) a dynamic loss modulus exceeding 250 Pa, 4) an average particle diameter exceeding 15 μm, and 5) a 90% particle diameter exceeding 35 μm. Consequently, there is a problem that conventional tofu pastes have a poor texture, being gritty, and acidic drinks compounding such tofu pastes have a poor texture and flavor, and moreover separation of components occurs during storage.
Moreover, with a paste obtained by adding a coagulating agent to soy milk and then homogenizing with a homogenizer, because the paste is produced using only a homogenizer, the average particle diameter exceeds 15 μm and the 90% grain diameter exceeds 35 μm, and hence there is a problem that an acidic drink compounding such a tofu paste has a poor texture and flavor.
Moreover, as mentioned above, an acidic soy milk drink obtained by adding a stabilizer to a soy protein liquid extract and then adding and mixing a fruit juice or an acidulant to the resulting solution, an acidic soy milk drink in which soy milk to which a high methoxyl pectin has been added is used as a raw material base, an acidic protein drink in which tamarind seed gum polysaccharide and/or guar gum and a pectin are used together, and so on are known; however, with such acidic protein drinks, there is a problem that, due to coagulation and precipitation of the protein under the acidic conditions, the texture and flavor thereof are poor, and separation of components occurs.
Moreover, as mentioned above, a fruit juice-containing soy milk drink obtained by adding an acidic fruit juice and an organic acid to soy milk that has been fermented using lactic acid bacteria, an acidic milk drink in which a pectin and gum arabic are used as stabilizers, and so on are known; however, with such acidic drinks, for example, in the case of a high-protein soy milk drink, there is a problem that the texture and flavor thereof become poor due to coagulation and precipitation of the protein.
As described above, various methods of manufacturing tofu paste and methods of manufacturing acidic drinks containing soybean products such as tofu paste have been proposed hitherto, but for example, there have been problems with conventional products in terms of texture and flavor in particular as described above; in the technical field in question, there have thus been strong demands for the development of a completely new type of product not having such problems.
Amid such a state of affairs and in view of the prior art described above, the present inventors carried out assiduous studies with an aim of developing novel acidic drinks according to which the problems seen with conventional products described above can be reliably resolved, and as a result discovered that when manufacturing acidic drinks containing a soybean product, by using a tofu puree having specific physicochemical properties as a raw material, acidic drinks of a novel type having an excellent texture and a favorable flavor can be manufactured, thus accomplishing the present invention.
That is, it is an object of the present invention to provide acidic drinks that contain a tofu puree having specific physicochemical properties and thus have improved texture and flavor.
Moreover, it is an object of the present invention to manufacture and provide acidic drinks having excellent product characteristics that cannot be expected with conventional products, namely a good texture and flavor, and being free from the separation of components during storage, by compounding a tofu puree having specific physicochemical properties as a raw material when manufacturing acidic drinks containing a soybean product.